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Comment by atdt | Hacker News Reader

It's less complicated than you might think. You call into SQLite C library functions using C calling conventions. Here's the relevant code: https://asm32.info/fossil/asmbb/file?name=source/sqlite3.asm...

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How about for setting up a server and serving http requests / establishing web sockets?

If it’s just a bunch of calling C code then I have to ask which part of this is actually assembly

To be fair, from that perspective every backend web application in every language is really just "calling C code".

That's overly simplistic and untrue. If you write a C# / .Net program you're not "just calling C code", you're not calling C at all.

but then your runtime VM calls C :)

But the CLR is written c, c++ and assembly which is what runs c#. Also the syscalls that run down the chain are also written in c, c++ etc.

That is just the runtime. That is smaller of fraction of what is going on when your programs execute than you think.

The C# code you write (and majority of the your code's dependencies) are JIT compiled to native machine code (or more recently there are AOT compilation options).

You can ask the same about e.g. Pascal, Python and Javascript, because all of them just make a bunch of C calls at the end of the day and can’t use NIC ports directly.

To do this in assembler you write raw syscalls to bind to open the TCP stream and then accept to handle incoming connections, possibly with fork or clone3 to spawn a process/thread to handle the new connection. None of that requires C programming. HTTP is "just" some text parsing on top of read/write calls to the file descriptor returned by accept. Web sockets are "just" some connection logic on top of HTTP.

A basic implementation of that is totally possible in assembly with no calls to c libraries. Would even be a great project for people to learn some systems programming. Keep in mind, all of these protocols (except maybe web sockets) were designed when programming in assembler was common. There's probably some HTTP implementation in the wild doing the same thing.

That said there's a lot of reasons you probably don't want to do that, HTTP can be subtle and you probably don't want to be doing raw clone3 calls to spawn threads, if you want to be doing thread or process per connection in the first place.

Well, you see, most OSes today aren't written in ASM. Their native libraries are C, so you have to interface with those libraries if you want to utilize them and their features.

You can certainly write your own TCP/IP stack with raw sockets and directly interface with the NIC, if you like. But at that point you're both reinventing the wheel and bypassing the entirety of the OS, you might as well just write a forum exokernel.

Most developers don't consider utilizing a library in another language as "cheating". Popular and core Rust, D, C++, Python, nodeJS, etc libraries do this all the time.

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